Chock mechanism for vehicle lifts



1951 G. A. ESTEL, JR

' CHOCK MECHANISM FOR VEHICLE LIFTS Filed Aug. 5, 1949 0mm WW 4! n? M ww Patented Oct. 2, 1951 CHUCK MECHANISM FOR VEHICLE LIFTS George A.Estel, Jr., Des Moines, Iowa, assignor to Globe Hoist Company, DesMoines, Iowa, a.

corporation of Iowa Application-August 3, 1949, Serial No. 108319 4.Claims. (Cl. 25489) This invention relates generally to; vehicle lifts land in particular to a chock means for automatically blocking the endsof the vehicle supporting rail in a lift, asthe: lift is elevated.

An object of; this invention is to. provide a wheel chock mechanism.which is automatically operated in responseto the raising and loweringmovements of a lift.

Another object of this invention is to. provide a gravity-actuatedchock. mechanism for a verhicle lift in which a: pivoted: wheel chockmemher is locked in: its checking position against movement in opposite;directions, and released for movement to a non-chockingposition inresponse to the upward movement/10f a ground. engaging counter-weightedarm.v

A further. object-of thislinvention isto-provide a chockmechanism for. avehicle lift; the-operating-members of whichare-im open assembly belowthe chock member and' outwardly from the vethiclesupporting track-:so.as-tobe free of any dirt accumulations and. in particular of the foreignmaterial removed from. avehicle during; body washing and chassis.steaming operations.

Yet another object. of this invention is to provide a chocking mechanismfor a vehicle-lift having a track with a hinged ramp, in which a pivotfor a pivoted chock member, assembledw-ith the ramp, the pivot for theramp, and the'actuating mechanism for. thechock member arelocatedbelowthe chock member and outwardly from the break between:the track. andthe. ramp so that washings from the track are permitted to drop directlyto the ground withoutpassing over any of the pivots in the chockmechanism.

A feature of this inventionisfoundrin the provision of a chock.mechanism for a vehicle lift having a vehicle track withia rampsupportprojected longitudinally from one end thereof. A transverse pivot foraramp is carried .on2the support at a position outwardly from the track,with the support being constructed to engage and limit the downwardpivotal movement of the ramp. A pivoted chock member has a pivot on theramp support co-axial with thetramp piv- 0t and is movable to a firstpositionin the plane of the ramp and to a second upright position at theend of the track. Acam on thelower-side of the chock memberisiengagea-ble with-a" follower atone end of a pivoted actuating, arm;atransverse pivot for whicharm is:carried on: the ramp support at aposition spaced outwardly" and downwardly from. the chock. pivot; Theother end of the arm carries a ground-engaging weight so that asthe.lift-iswelevated.the followerris moved upwardly against: the: cam toin turn move the chock to its upright position,.which is defined by theengagement of a' downwardly projected stop on the chock with the pivotfor the actuating arm. At this uprightposition. the follower is receivedwithin a recessed: portion on" the cam, arranged relativeto the pivots;for'the chock and the actuating arm such' that the chook is lockedagainst being moved by' any pressure: exerted thereon by a: vehiclewheel. However; as. the lift is lowered,and the weighted end of the."arm engages the ground, the? follower is moved outwardly anddownwardlyout of'thercam recess-to permit the pivotal movement; of; thechock; into the plane of the ramp;

Further objects, features; and; advantages of this invention will becomeapparent: from. the following description: when: taken: in connectionwith the accompanyingjdrawingsq in which:

Fig. I is a' perspective: view' of a vehicle lift embodying the chockmechanism of thisiinvention, with the chocksbeingillustratedlinwheelblocking positions:

Fig. 2 is an enlarged. foreshortened sectional view of the chockmechanism? asrseen alongthe line 2-2 in Fig. 1-;

Fig. 3 is a sectional viewillustrated similarly,

to Fig. 2 showing parts of thechock mechanism in changed positions;

Fig. 4 is an enlarged foreshortene'd' sectional view as taken-along. the1ine:4*-4 inFlg. .2; and

Figs. 5, 6 and 7 are sectionatdetail views taken along the lines 5-5;6-'-6 andl1''l;-respectively, in Fig. 4.

With referenceto 1 of? the? drawings, the automatic wheel chockmechanism"- of this invention is illustrated in. assembly with aconventional automobile: lift. of roll-om type" including a pair. oflongitudinal. tracks or" runways l0 carried on a plunger M 'Iheplungerisoperated by a suitable means (not shown) to: raise andlower the lift.

A chock mechanism of thisinvention, designated generally atl2 in-wFig;1-; is assembled at each end of a wheelsupporting'track Ill; Since eachmechanism is' of a like construction. and similarly assembled onrthelift; onlyone? of! them will be described in detail.

A chock mechanismt I2 inoludesiaipairof sup"- ports or-mounting bracketsl3; and 13a (Figs. 2, 4 and 6) secured to: theaundersidei of a track. I.0 1 in a transversely spaced relation and projectedllongitudinallyoutwardly: from. an 1 end of" thetrack. Each bracket: l S andISaincludsa horizontal top portion: I 41 attached by bolts I 6 to.theitra'cki l0,

and an upright body member I1 projected downwardly from the horizontalportion l4. Substantially intermediate the ends of a body member I! area pair of vertically spaced laterally extended bearing sleeves l8 andI9, with the sleeve |9 being located downwardly and out" wardly from thesleeve IS. The brackets I3 and |3a are of a left and right hand type, sothat in the assembly of a pair of such brackets on the end of a trackII], the bearing sleeves l3 and l9 on a pair of corresponding bracketsi3 and Illa project inwardly toward each other, as best appears in Fig.4.

The top side of the forward end 2| of a bracket I3 and |3a, and asindicated at 25 in Fig. 6, is inclined downwardly and forward-1y for apurpos which will appear later. It will further be noted that thesleeves I8 and I9 are carried in that part of the body member H whichextends outwardly from the end of the track iii.

The bearing sleeves l8 and |9 in a corresponding pair of brackets .|3and |3a are in co-axial alignment, with a pivot rod 22 (Fig. 4) beingcarried in the bearings l8 and a pivot rod 23 in the bearings I9. Ahinged or pivoted ramp 24 (Figs. 3, 4 and '7) is provided on the underside of its upper end 26 with a pair of transversely spaced mountings2'! integrally formed withsleeve'bearings 28; The spacing of themountings 2! is such that the supporting brackets 13 are receivabletherebetween, with the bearings 28 in"co-axial'alignment with thebearings l8. 'The' pivot rod 22 extends outwardly from the bearings 8and into the bearings 28 whereby to support the ramp 24 for pivotal upand down movement relative to the brackets l3 and l3a. r

The inner end 26 of the ramp 24 is formed with a cut-away portion 29(Figs. 1 and 2) to receive therein a pivoted chock member 3|. The chockmember 3| (Figs. 1, 2 and is of a generally flatshape and integrallyformed with a pair of transversely spaced downwardly projected side orear members 32, which are formed adjacent their inner ends 33 withaligned openings 34 for receiving the pivot rod 22. The transversespacing of the side members 32 is such that they arelocated-between the mounting brackets l3 and l3a.

' The outer end 36 of the wheel chock 3| (Fig. 4) is integrallyformed'with'laterally extended projections 31, with this outer end 33"and the projections 31 being receivable within a transverse depressionor pocket 38 formed in the outer side wall of the ramp cut-away portion29. The depression' 38 is of adepth such that when thechock end 36 isreceived therein the chock me'mber'3l is in substantially the plane ofthe ramp 24. By virtue of the pivoted support of the chock member3l onthe pivot 22, at a position adjacent the inner end of the chock member,it is pivotally movable to a substan tially upright position at the endof the track 5 3. The upright position of the chock member 3| isdetermined by the engagement of a stop member 39, inclined downwardlyfrom the inner end of the chock, with the pivot rod 23 which pivotallysupports a counter-weighted arm structure 42. The stop 39 is locatedintermediate the sides of the chock member 3|, with the pivot rod 22being inserted through an opening 45 therein (Fig. 4).

The arm structure 42- is comprised of a pair of transversely spaced armmembers 43 (Fig. 4) arranged-inwardly of the. side-members 32 of 4 thechock member 3|, and pivoted intermediat their ends on the pivot rod 23which is carried in the sleeve bearings I9. Mounted between the innerends of the arms 43 is a ground engaging counter-weight 44 of a rollerconstruction. Supported between the outer ends 46 of the arms 43 is ashaft 41 which projects laterally from the arms 43, and has rollers 48mounted on its projected ends. These rollers or cam followers 48 .areengageable with cam members 49 supported from the underside of the wheelchock 3| at positions adjacent to the side members 32 (Figs. 3 and 4).The cams 49 are of a like construction and are formed adjacent theirinner ends with pockets or recessed portions 5| for a purpose to appearlater.

In the operation of the chock mechanism of this invention, assume thatthe track H] is in its lowermost position, illustrated in Fig. 3, withthe outer end of th ramp 24 resting upon a ground or floor surface,indicated at 53. At this lowered position of the lift, or track Hi, thewheel chock 3| is substantially in the plane of the ramp 24, while thearm structure 42 is extended longitudinally of the track in asubstantially horizontal position, and with the roller weight 44 locatedbeneath the track and resting on the ground surface 53.

On elevation of the lift, the arm structure 42 is pivoted in acounter-clockwise direction, as viewed in Fig. 3, by the action ofgravity on the weight 44. As a result of this movement, the rollers 48are moved upwardly into engagement with the cams 49, whereby the wheelchock 3! is pivotally moved from its position shown in Fig. 3 to itsupright position shown in Fig. 2. This counter-clockwise movement of thearm structure 42 is limited by the engagement of the stop member 39 withthe pivot rod 23 so as to positively lock the chock member 3| againstfurther pivotal movement in a counter-clockwise direction about itspivot 22. With the chock member 3| in an upright position, the rollers48 are received within the pockets 5| of the cam members 49, and thoseportions 52 of the arm members 43, located between the pivot rod 23 andthe rollers 48, are in substantiallyupright positions. As a result, anyforce applied against the wheel chock 3| by a vehicle wheel is incapableof moving the wheel chock 3| toward the ramp 24 by virtue of thesubstantial vertical alignment of the pivot 23 and the roller shaft 41.

It is seen, therefore, that the wheel chock 3| is positively lockedagainst movement in a counter-clockwise direction about the shaft 22 bythe stop member 39 and is releasably locked against movement in aclockwise direction by virtue of the construction of the cam 49', armstructure 42 and their assembly relative to the pivot23 and roller shaft41. The downward pivotal movement of the ramp 24 is limited; by theengagement of its underside with the top surface portions 25 of themounting brackets I3 and |3a. (see Fig. 6.)

When the lift is lowered, the weight 44 is initially engaged by theground surface 53 and the arm structure 42 is pivoted in a clockwisedirection about the pivot 23. This pivotal movement i accomplished byvirtue of the fact that the weight 44 is located inwardly of the pivot23 when the chock 3| is in its upright position. As a result of thisclock-wise movement of' the arm structure 42 the rollers 48 are movedoutwardly and downwardly out of engagement with-the pockets 5i inthecams 49:, wherebythe chockti is permitted todrop by. the action ofgravity from its upright positionshown in Fig. 2 to its posi;- tion inthe plane of: the ramp24, as illustratedin Fig. 3-.

With reference to Figs. 2 and 3 it is. seen, that the construction andrelative assembly of the chock mechanism provides for the pivots, and231 being located at all times below the chock member 31. and outwardlyfrom the breakwor space 55i'between the end of the track Hi: anditheinner end of the ramp 24. Thu any washings or drainage from the trackI0, when the lift is in either a loweredor raised position, is permittedto drop to the floor surface 53 without at n time passing over thepivots 2,2; or 23 or the rollers 49. Further, and from a considerationof Fig. 4, it is seen, that the assembly of the chock mechanism isentirely open so as to prevent any dirt or grease accumulations.

From a consideration of the above description it is seen that theinvention provides a chock mechanism which is completely automatic inits operation in response to the lowering'and raising movements of alift, and which, in a checking position, is positively held againstmovement in a fixed position. However, in response to the engagement ofthe roller 44 and arm structure 42 with the ground surface 53, the chockmember 3| is released for dropping into the plane of the ramp 24 so thatin a lowered position of the lift, the chock member offers noobstruction to the passage of a vehicle to and from the tracks l9.

Although the invention has been described with respect to a preferredembodiment thereof, it is to be understood that it is not to be solimited since changes can be made therein which are within the fullintended scope of this invention, as defined by the appended claims.

I claim:

1. In a vehicle lift having a track for supporting a vehicle to beelevated and a pivoted ramp, means pivotally supporting said rampoutwardly from one end of said track for up and down pivotal movement, achock member pivoted on said supporting means for movement about atransverse axis common to said ramp, for pivotal movement into and outof the plane of said ramp, an arm structure extended longitudinally ofsaid track pivoted intermediate the ends thereof on said supportingmeans for up and down movement, with the pivot for said arm structurebeing at a position spaced outwardly and downwardly from said commonaxis so that the outer end of said arm structure is below said chockmember and the inner end of said arm structure is below said one end ofthe track, a weight at the inner end of said arm structure engageablewith a ground surface, a cam. follower on the outer end of said armstructure, a cam member on the lower side of said chock member having alocking portion thereon, with said cam follower being engageable withsaid cam member and movable into said locking portion in response to anupward movement of said cam follower, whereby to pivotally raise saidchock member upwardly from said ramp, and co-acting stop means on saidarm structure pivot and chock member to define a moved position of saidcam follower within said cam locking portion.

2. In a vehicle lift having a vehicle supporting track, a mountingbracket supported on said track and projected longitudinally outwardlyfrom one end thereof, a first transverse pivot carried on said bracketoutwardly from said one end of the said; second. p t andtended lon itudielly of aid r ck; s that. he o t r en of. said: tructure b low aid hoa sm mber a d the inn r nd of saidlarm's ruet re isibelew sa one en of, t ak, a r und. eneaein vwei said in rn of; h armstruc ure; cal. fol: loweronthe outer end of saidarm'sinu ture cam. memb r projected ow war ly 'imsaid hockmember and. ensable hr said cam-fol;- lower on upwend.movement of the outer end said; arm, structure in; response to, the, aptravityv on, the, nner nd. of. aid. arm: s-tr as e ift iseleva ed; wh rby to; pivotaliy raise th h ck, member ut i h plane-of: said-rains. alocking portion on said cam member for releasably locking said camfollower to hold said chock member against movement into the plane ofsaid ramp, and co-acting means on said chock member and secondtransverse pivot for limiting the upward movement of said chock memberat said locking position of the cam, with said cam follower beingreleased in response to a downward movement of the outer end of said armstructure as effected by the engagement of the inner end of the armstructure with the ground when the lift is lowered.

3. In a vehicle lift having a wheel supporting track and a pivoted rampextended longitudinally outwardly from one end of the track, anautomatic chocking means including a chock member pivotally supportedfrom said track at a position outwardly from said one end of the trackfor pivotal movement to a first position substantially in the plane ofsaid ramp and to a second substantially upright position, a cam memberprojected downwardly from said chock member having a locking portionformed thereon, a pivoted arm structure extended longitudinally of saidtrack and supported intermediate the ends thereof from said track sothat the outer end of said arm structure is below said chock member andthe inner end of said arm structure is below said one end of the track,a ground engaging weight at the inner end of said arm structure, afollower portion at the outer end of said arm structure engageable withsaid cam in response to an upward movement of the lift, whereby to movesaid chock member toward said second position therefor, said followerportion at said second position being receivable within said cam lockingportion, with the pivot supports for said chock member and arm structurebeing arranged relative to said cam locking portion such that the chockmember in said second position therefor is releasably locked againstmovement toward said first position therefor, said follower portionbeing movable out of said locking portion to release said chock memberfor movement to said first position therefor in response to a downwardmovement of said follower portion as effected by the engagement of theweighted inner end of said arm structure with the ground when the liftis lowered.

4. In a vehicle lift having a wheel supporting track with a pivoted rampat one end thereof, an automatic chock means including a pair oftransversely spaced brackets secured to the under side of said track andprojected longitudinally outwardly from said one end thereof, a trans- 7verse pivot forsaid ramp carried on said brackets outwardlyfrom said oneend of the track, a chock member pivotally supported on said pivot formovement to a first position substantially in the plane of said ramp andto a second substan tially upright position, a second transverse pivoton said brackets spaced outwardly and downwardly from said first pivot,an arm structure extended longitudinally of said track between saidbrackets and pivotally supported intermediate the ends thereof on saidsecondpivot for up and down pivotal movement, a weight at the inner endof said arm structure, a cam follower portion on the outer end of saidarm structure, a downwardly extended stop member on said chock memberengageable with said second pivot to define the second position of saidchock member, a cam member on the underside of said chock member havinga locking portion formed therein, with said follower portion beingengageable with said cam member by the action of gravity on the weightedinner end of said arm structure as the lift is elevated, whereby to movesaid chock member to said second position therefor, said cam followerportion at said second position of the chock member being receivable insaid looking portion to releasably lock said chock member againstmovement toward said first position therefor, and being movableoutwardly from said locking portion in response to the engagement of theweighted inner end of said arm structure with the ground when the liftis lowered.

GEORGE A. ESTEL, JR.

REFERENCES CITED UNITED STATES PATENTS Name Date Number Hott et a1. Apr.17, 1934

